#include <LiquidCrystal_I2C.h>
#define MQ2_ANALOG A1
#define MQ2_DIGITAL 2

LiquidCrystal_I2C lcd(0x27, 16, 2);

void setup() {

  Serial.begin(9600);
  pinMode(MQ2_ANALOG, INPUT);
  pinMode(MQ2_DIGITAL, INPUT);

  lcd.init();
  lcd.backlight();
}


void loop() {

  int MQ2_ANALOG_X = analogRead(MQ2_ANALOG);
  int MQ2_scaledValue = map(MQ2_ANALOG_X, 0, 1023, 0, 100);

  lcd.clear();
  lcd.setCursor(0, 0); 
  lcd.print("Detector de gases");

  lcd.setCursor(0, 1);
  lcd.print("Gas: ");
  lcd.print(MQ2_scaledValue);
  lcd.print("%");

  delay(500);

}